Machine Language Manager (MLM) is a 2KB cartridge written by Andy Guevara in 1981 for the Bally Arcade/Astrocade. It was released by The Bit Fiddlers in late 1981/early 1982.
This video explains how to use the Machine Language Manager cartridge, a machine language monitor that allows direct access to programming the Z80 CPU. This cartridge does not require extra memory to use it, but it can take advantage of extra RAM if it is available.
"The Bally/Astrocade Game Cartridge and Hardware FAQ" says this about the MLM:
"This cartridge, which included [a 24-key keypad] overlay, provides an "easy" way to program the Astrocade in machine language. Though not a Z-80 assembler, MLM does simplify the entry of hex code (which otherwise must be entered using decimal via BASIC. Also, the keypad layout does not require the use of the key-shifts, so typing is faster). Programs can be saved via the Bally BASIC 300-baud interface (later, subroutines were written that allowed the 2000 baud version of Bally BASIC (#6004) to be swapped out for tape saving). "Machine Language Manager" does NOT have a built-in cassette interface."
This overview is part two of a four part series. The series includes:
Machine Language Manager, Part 1: Overview and Background
Machine Language Manager, Part 2: How to Use the MLM
Machine Language Manager, Part 3: Using MLM Example Programs
Machine Language Manager, Part 4: Using MLM with the Astrocade MAME Emulation
This video is split into several parts:
0:0:00 - "How to Use the MLM" Titles 0:0:15 - Short Introduction to the MLM Video Series 0:0:44 - Overview of the MLM Manual 0:13:00 - Using the MLM: Section 1
- What is the MLM - The Start-Up Screen - Usable RAM vs. Lines Per Screen - MLM Keypad Overlay - MLM Commands: ADDR., WRITE, READ and LIST
0:23:27 - Using the MLM: Section 2
- Examining ASCII Text in ROM - Changing MLM Defaults - Debugging a "Program" - MLM Command: REG.
0:43:03 - Using the MLM: Section 3
- Using the MLM Assembly Listing - Using a SYSTEM Routine - Using RECTAN - Typing in Example 5-1 - A Splash of Green
0:49:31 - Using the MLM: Section 4
- The User Program Interface (UPI) - FILL (Subroutine $1A)
1:00:00 - Using the MLM: Section 5
The User Program Interface (UPI)
- MOVE (Subroutine $5E) - (aka Copy)
1:07:12 - Using the MLM: Section 6
- An MLM Single Byte CALL - STRING (Print String)
1:24:20 - Using the MLM: Section 7
- Saving an ML Program with the 300-Baud Tape Interface - No Tapes; Using WAV Files - Saving/Loading a Program - Checking a Program - Running a Program
1:35:39 - MLM: Wrap-Up and Preview of Parts 3 and 4 1:36:48 - End Credits
This video is aimed at someone who has little or no understanding of Z80 machine language. A Z80 machine language programming novice, or anyone who has a passing interest in using the Machine Language Manager cartridge, will get more out of it if all of the four videos in this series are watched one after the other. Also, even if you have no plans to ever use the Machine Language Manager cartridge, anyone who wanted to know how to program the Astrocade will find plenty of general information provided in this video.